North Korea is in the continent of Asia.
The system which was in practice was the Shogunate system. It was between the two restorations and was about Shoguns who were military leaders. The period was marked by sever isolation and it ended during the Meiji restoration when the Shogunate ended.
Sentence 2 should be followed by a citation. The reason why this sentence should be followed by a citation is because there needs to be proof that Truman did in fact feel this way. Usually this sentence would be a paraphrase or summary from a primary source. Without a citation, one could argue that this was not the way Truman felt.